Reaktion #1278795

Reaktionsgleichung

ammonium fluoride

5-amino-1H-quinolin-2-one

3,3,3-trifluoro-2-hydroxy-2-methoxymethypropan-1-one

acetic acid

→

5-[(3,3,3-trifluoro-2-hydroxy-2-methoxymethyl-1-phenylpropylidene)amino]-1H-quinolin-2-one

Lösungsmittel

Ethyl acetate

toluene

1,4-dioxane

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturThe mixture is heated over 20 hours to 110° C.
2. 2
   SonstigePhases are separated
3. 3
   Extraktiontwo times extracted with ethylacetate
4. 4
   EinengenThe combined organic phases are concentrated

Vorschrift

To 194 mg (1.2 mmol) 5-amino-1H-quinolin-2-one and 300 mg (1.2 mmol) 3,3,3-trifluoro-2-hydroxy-2-methoxymethypropan-1-one in 4 ml toluene and 1 ml 1,4-dioxane are added 0.26 ml acetic acid and 1 ml tetrabutyl orthotitanate. The mixture is heated over 20 hours to 110° C., cooled to room temperature and poured into aqueous ammonium fluoride solution. Ethyl acetate is added and the mixture is stirred vigorously for 30 minutes. Phases are separated and two times extracted with ethylacetate. The combined organic phases are concentrated to yield quantitatively 5-[(3,3,3-trifluoro-2-hydroxy-2-methoxymethyl-1-phenylpropylidene)amino]-1H-quinolin-2-one. 396 mg (1 mmol) imine in 22 ml methanol is cooled to 5° C. and 700 mg sodium boron hydride are added in multiple portions over the period of 24 hours. The reaction is quenched by addition of saturated ammonium chloride solution and diluted with water and ethyl acetate. The phases are separated, the aqueous layer is extracted with ethyl acetate, the combined organic phases are washed with brine and dried over sodium sulphate. After removal of the solvent flash chromatography on silica gel (ethyl acetate in hexane 0 to 80%) yields 53 mg of the title compound.

Quelle